All eligible women (age 18 and older) seen in the obstetric clinic at Johns Hopkins University between November 1983 and January 1985 who agreed to participate had their cervix evaluated for signs of inflammation. In addition cultures were taken for a number of aerobic and anaerobic organisms and a sample of cervical mucus was evaluated for the presence of inflammatory cells. The women were interviewed to obtain information on a number of risk factors related to preterm and low birth weight delivery. The women were then followed to delivery to evaluate the effect of cervicitis on preterm or low birth weight delivery. Approximately 800 women participated in this study. Data tapes have been provided by John Hopkins and data editing programs have been developed. Analysis began in August 1985 with articles to be submitted for publication as soon as possible.